Vector flush sizing catheter and method

ABSTRACT

The techniques of this disclosure generally relate to a vector flush sizing catheter that is used initially to disperse contrast and measure a length of a main vessel using radiopaque measuring markers of the catheter. Subsequently, the vector flush sizing catheter is used to guide and introduce another endovascular device into the main vessel. By using the vector flush sizing catheter for both procedures, the exchange of catheters, the complexity of the procedure, and the associated risks are minimized.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/655,893, filed on Apr. 11, 2018, entitled “VECTOR FLUSH CATHETER ORATG SIZING CATHETER” of Della Vecchia, which is incorporated herein byreference in its entirety.

FIELD

The present technology is generally related to an intra-vascular deviceand method. More particularly, the present application relates to adevice for treatment of intra-vascular diseases.

BACKGROUND

A conventional stent-graft typically includes a radially expandablereinforcement structure, formed from a plurality of annular stent rings,and a cylindrically shaped layer of graft material defining a lumen towhich the stent rings are coupled. Stent-grafts are well known for usein tubular shaped human vessels.

To illustrate, endovascular aneurysmal exclusion is a method of using astent-graft to exclude pressurized fluid flow from the interior of ananeurysm, thereby reducing the risk of rupture of the aneurysm and theassociated invasive surgical intervention.

To deploy the stent-graft, multiple exchanges of catheters arenecessary. Each exchange includes the potential for blood loss,complicates the procedure, and takes time.

SUMMARY

The techniques of this disclosure generally relate to a vector flushsizing catheter that is used initially to disperse contrast and measurea length of a main vessel using radiopaque measuring markers of thecatheter. Subsequently, the vector flush sizing catheter is used toguide and introduce another endovascular device into the main vessel. Byusing the vector flush sizing catheter for both procedures, the exchangeof catheters, the complexity of the procedure, and the associated risksare minimized.

In one aspect, the present disclosure provides a catheter including ahandle. A guide tube is coupled to the handle. A guide passage extendsthrough the handle and through the guide tube. A steering assembly isconfigured to deflect a distal bendable part of the guide tube. At leastone contrast flush hole is in a straight part of the guide tube.

In another aspect, the present disclosure provides a catheter includinga handle. A guide tube is coupled to the handle. A guide passage extendsthrough the handle and through the guide tube. A steering assembly isconfigured to deflect a distal bendable part of the guide tube. Aplurality of regularly spaced apart radiopaque measuring markers are ona straight part of the guide tube.

In yet another aspect, the present disclosure provides a methodincluding bending a distal bendable part of a guide tube of a catheterso that an opening at a distal end of the guide tube is directlyadjacent at least one contrast flush hole in the guide tube. Contrast isdispersed through the opening and the at least one contrast flush hole.Radiopaque measuring markers on the guide tube are visualized. Anendovascular device is guided through a guide passage of the guide tube.

The details of one or more aspects of the disclosure are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the techniques described in this disclosurewill be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side view of a vector flush sizing catheter in accordancewith one embodiment.

FIG. 2 is an enlarged perspective view of a distal portion of a guidetube of the vector flush sizing catheter of FIG. 1 in accordance withone embodiment.

FIG. 3 is a cross-sectional view of the guide tube along the line ofFIG. 2 in accordance with one embodiment.

FIG. 4 is a cross-sectional view of the guide tube along the line IV-IVof FIG. 2 in accordance with one embodiment.

FIG. 5 is a side plan view of the vector flush sizing catheter with theguide tube deflected in accordance with one embodiment.

FIG. 6 is a partial cross-sectional view of a vessel assembly includingthe vector flush sizing catheter of FIG. 1 in accordance with oneembodiment.

FIG. 7 is a partial cross-sectional view of the vessel assemblyincluding the vector flush sizing catheter of FIG. 6 after deployment ofan aortic bifurcated stent graft in accordance with one embodiment.

FIG. 8 is a partial cross-sectional view of the vessel assemblyincluding the vector flush sizing catheter of FIG. 7 during deploymentof a contralateral limb in accordance with one embodiment.

DETAILED DESCRIPTION

FIG. 1 is a side view of a vector flush sizing catheter 10 in accordancewith one embodiment. Referring to FIG. 1, vector flush sizing catheter10, sometimes called a steerable flushing sizing catheter 10, includes aflexible guide tube 12 carried by and coupled to a handle 14. Flexibleguide tube 12 may be constructed, for example, by extrusion usingstandard flexible, medical grade plastic materials.

Handle 14 may be constructed, for example, from molded plastic. Handle14 is sized to be conveniently held by a clinician, to introduce guidetube 12 into an interior body region that has been targeted fortreatment.

Vector flush sizing catheter 10 includes an open path through whichcontrast can be delivered and an endovascular device or tool can bedeployed for use. For this purpose, vector flush sizing catheter 10includes an interior guide passage 18. Guide passage 18 extends throughan interior portion of handle 14 continuously into and through guidetube 12. Entrance into guide passage 18 is provided by a proximalopening 20 formed in handle 14. Guide passage 18 terminates at anopening 22 at a distal end 70 of guide tube 12.

As used herein, the proximal end of a prosthesis is the end closest tothe heart via the path of blood flow whereas the distal end is the endfurthest away from the heart during deployment. In contrast and of note,the distal end of the catheter such as vector flush sizing catheter 10is usually identified to the end that is farthest from theoperator/handle 14 while the proximal end of the catheter is the endnearest the operator/handle 14.

For purposes of clarity of discussion, as used herein, the distal end ofvector flush sizing catheter 10 is the end that is farthest from theoperator (the end furthest from handle 14) while the distal end of theprosthesis is the end nearest the operator (the end nearest handle 14),i.e., the distal end of vector flush sizing catheter 10 and the proximalend of the prosthesis are the ends furthest from handle 14 while theproximal end of vector flush sizing catheter 10 and the distal end ofthe prosthesis are the ends nearest handle 14. However, those of skillin the art will understand that depending upon the access location, theprosthesis and vector flush sizing catheter 10 descriptions may beconsistent or opposite in actual usage.

Guide tube 12, while flexible, suitably has a plastic memory or biasthat normally orients the distal end region of guide tube 12 in anessentially straight configuration, as shown in FIG. 1. To enablegreater control of the orientation of the distal end region of guidetube 10, vector flush sizing catheter 10 includes a steering assembly24. In operation, steering assembly 24 deflects the distal end region ofguide tube 12 out of its essentially straight configuration and into abent or deflected configuration, as shown in FIG. 5 for example.

In its essentially straight configuration, guide tube 12 is welloriented for deployment into an interior body region, e.g., through anintra-vascular or cannulated access path. Upon deployment of guide tube12 to a desired body region and/or during such deployment, a cliniciancan operate steering assembly 24 to deflect the distal end region ofguide tube 12 in its bent or deflected condition.

Steering assembly 24 includes an actuator 26, a linkage system 28, and adeflecting component 30. Actuator 26 can be manipulated by theclinician. Actuator 26 is coupled through linkage system 28 todeflecting component 30, which is coupled to the distal end region ofguide tube 12.

It should be appreciated that actuator 26 of steering assembly 24 cantake many forms, such as a sliding lever or a pistol grip. Actuator 26can be located at many locations on handle 14, such as the proximal end,the distal end, or the mid-portion. In the embodiment shown in FIG. 1,actuator 26 takes the form of a fluted knob that is rotationallyattached to the distal end of handle 14. Actuator 26 is positioned sothat it can be rotated by the thumb of the clinician's hand that holdshandle 14.

In general operation, manual force applied by the clinician to actuator26 is translated by linkage system 28 into a pulling force or tensionexerted on deflecting component 30, which deflects or bends the distalend region of guide tube 12.

Vector flush sizing catheter 10 includes an in-line hemostatic valveassembly 52 at or near proximal opening 20 of passage 18. Valve assembly52 prevents blood or fluid loss by sealing proximal opening 20 when anoperative device or tool is within passage 18, as well as when nooperative device or tool is present in passage 18.

An infusion valve 58 is also coupled to passage 18. In this way, fluidcan be conveyed through passage 18 into the interior body region, e.g.,to flush materials from passage 18 during use. In one embodiment,contrast 60 is introduced through infusion valve 58 and into passage 18as discussed further below.

Although a particular structure deflecting or bending the distal endregion of guide tube 12 is illustrated in FIG. 1 and discussed above, inlight of this disclosure, those of skill in the art will understand thatother deflecting or bending structures are used in other embodiments.Examples of suitable deflecting and bending structures are set forth inBolduc, U.S. Pat. No. 9,320,503, issued Apr. 26, 2016, entitled“DEVICES, SYSTEMS, AND METHODS FOR GUIDING AN OPERATIVE TOOL INTO ANINTERIOR BODY REGION”, which is herein incorporated by reference in itsentirety. Also see the TourGuide™ steerable sheath sold by Medtronic,Minneapolis, Minn.

FIG. 2 is an enlarged perspective view of a distal portion 62 of guidetube 12 of vector flush sizing catheter 10 of FIG. 1 in accordance withone embodiment. FIG. 3 is a cross-sectional view of guide tube 12 alongthe line of FIG. 2 in accordance with one embodiment. FIG. 4 is across-sectional view of guide tube 12 along the line IV-IV of FIG. 2 inaccordance with one embodiment.

Referring now to FIGS. 1, 2, 3 and 4 together, guide tube 12 includes aradiopaque distal end marker 64, a plurality of radiopaque measuringmarkers 66, and one or more contrast flush holes 68, sometimes calledcontrast flush openings or apertures.

Radiopaque distal end marker 64 is located at the very distal end 70 ofguide tube 12 adjacent opening 22. Radiopaque distal end marker 64permits fluoroscopic visualization of the orientation of distal end 70of guide tube 12.

Radiopaque measuring markers 66 are regularly spaced apart radiopaquebands. Illustratively, each radiopaque measuring markers 66 is acomplete circle extending around the circumference of guide tube 12 in aplane perpendicular to a longitudinal axis LA of guide tube 12.

In one embodiment, a fixed distance D between adjacent radiopaquemeasuring markers 66 is 1.0 cm although fixed distance D has othervalues in other embodiments depending upon the desired scale to be used.In other words, the pitch, i.e., the center to center spacing betweenadjacent radiopaque measuring markers 66, is equal to fixed distance D,e.g., 1 cm. In one particular embodiment, there are 20 radiopaquemeasuring markers 66 each spaced 1.0 cm apart and so radiopaquemeasuring markers 66 are sometimes called 20 gold marker bands spacedone centimeter apart. However, more or less radiopaque measuring markers66 are used in other embodiments.

Radiopaque measuring markers 66, sometimes called gold marker bands 66,are formed of a radiopaque material, e.g., gold or other radiopaquematerial. Accordingly, radiopaque measuring markers 66 can be visualizedusing fluoroscopy. Radiopaque measuring markers 66 provide a ruler ormeasuring device to measure various anatomical features and variousstructures relative thereto as discussed further below.

Paying particular attention to FIGS. 3 and 4, contrast flush holes 68extend from guide passage 18 within guide tube 12 through the entiretyof guide tube 12 in the radial direction. More particularly, contrastflush holes 68 extend from an inner cylindrical surface 72 to an outercylindrical surface 74 of guide tube 12. Contrast flush hole 68 allowcontrast 60 to be flushed from guide passage 18 within guide tube 12 tothe exterior of guide tube 12. As discussed above, contrast 60 isintroduced into guide passage 18 through infusion valve 58.

In accordance with this embodiment, at any particular location alonglongitudinal axis LA of guide tube 12, there are more than one contrastflush hole 68, i.e., a plurality of contrast flush holes 68. Moreparticularly, at a particular location along longitudinal axis LA, thereis a pair of opposing contrast flush holes 68 opposite one another,i.e., at 180 degrees apart. However, in another embodiment, there isonly a single contrast flush hole 68 at any particular location alonglongitudinal axis LA. In another embodiment, there are more than two,e.g., three or four, contrast flush holes 68 at any particular locationalong longitudinal axis LA.

Further, in accordance with this embodiment, one or more contrast flushholes 68 are located along longitudinal axis LA at two or morelocations. For example, contrast flush holes 68 include four contrastflush holes 68A, 68B, 68C, and 68D. As illustrated in FIGS. 2, 3 and 4,at a first longitudinal location L1, there is a first pair of opposingcontrast flush holes 68A, 68B and at a second longitudinal location L2,there is a second pair of opposing contrast flush holes 68C, 68D.Contrast flush holes 68A, 68B (first longitudinal location L1) areadjacent to and distal to the most distal radiopaque measuring marker66A of radiopaque measuring markers 66. Radiopaque measuring marker 66Ais sometimes called a first radiopaque measuring marker 66A.

Contrast flush holes 68C, 68D (second longitudinal location L2) areadjacent to and between first radiopaque measuring marker 66A and asecond most distal radiopaque measuring marker 66B of radiopaquemeasuring markers 66. Radiopaque measuring marker 66B is sometimescalled a second radiopaque measuring marker 66B and is directly adjacentand proximal to radiopaque measuring marker 66A. In one embodiment,there are one or more contrast flush holes 68 between first and secondradiopaque measuring markers 66A and 66B.

In one embodiment, the radial orientation of contrast flush holes 68A,68B is radially offset with the radial orientation of contrast flushholes 68C, 68D. For example, contrast flush holes 68A, 68B are radiallyoffset by 90 degrees with respect to contrast flush holes 68C, 68D.Accordingly, in the view of FIG. 3, contrast flush holes 68A, 68B arehorizontally aligned whereas in FIG. 4, contrast flush holes 68C, 68Dare vertically aligned. By radially offsetting contrast flush holes 68,contrast 60 is locally dispersed regardless of the radial orientation ofguide tube 12. Although a 90-degree radial offset is illustrated anddiscussed, in light of this disclosure, those of skill in the art willunderstand that contrast flush holes 68 can be radially offset with moreor less than 90°.

In another embodiment, one or more, e.g., all, of contrast flush holes68 are radially aligned. For example, as indicated by the dashed circle68C-1 in FIG. 2, contrast flush holes 68A, 68B are radially aligned withcontrast flush holes 68C-1, 68D.

In FIGS. 3 and 4, deflecting component 30 is illustrated as extendingwithin a lumen of guide tube 12. Such an arrangement is simplyillustrative, and deflecting component 30 and/or other structures can berouted to distal end 70 of guide tube 12 in other manners in otherembodiments.

FIG. 5 is a side plan view of vector flush sizing catheter 10 with guidetube 12 deflected in accordance with one embodiment. As illustrated inFIG. 5, the clinician rotates actuator 26 to bend, sometimes calledsteer, a distal bendable part 76 of guide tube 12. In accordance withthis particular embodiment, guide tube 12 is bent such that distalopening 22 is facing 180° as compared to guide tube 12 in the unbent(straight) configuration as illustrated in FIG. 1.

In one embodiment, distal bendable part 76 of guide tube 12 is distal tothe distal most contrast flush holes 68, i.e., is distal to contrastflush holes 68A, 68B in this embodiment. Accordingly, contrast flushholes 68 and radiopaque measuring markers 66 are on a straight part 78of guide tube 12. Although straight part 78 is illustrated and discussedas being straight, in light of this disclosure, those of skill in theart will understand that straight part 78 may be deflected or bentpassing through the anatomy as discussed further below. Generally,distal portion 62 of guide tube 12 includes distal bendable part 76 andstraight part 78 proximal to distal bendable part 76.

Further, once distal bendable part 76 is bent 180 degrees as illustratedin FIG. 5, distal opening 20 is longitudinally located adjacent to thefirst radiopaque marker 66A and between contrast holes 68. This allowscontrast 60 to be dispersed from distal opening 20 and contrast holes 68in a localized manner as discussed further below.

FIG. 6 is a partial cross-sectional view of a vessel assembly 600including vector flush sizing catheter 10 of FIG. 1 in accordance withone embodiment. Vessel assembly 600 illustrates a series of vesselswithin the human body, including the aorta 602, the renal arteries 604,606, and the common iliac arteries 608, 610. More particularly, theaorta 602, sometimes called a main vessel 602, descends from the renalarteries 604, 606, sometimes called branch vessels, 604, 606, to anaortic bifurcation 612 from which extend common iliac arteries 608, 610.Aortic bifurcation 612 is sometimes called a main vessel bifurcation612.

In accordance with this example, aorta 602 includes an aneurysm 614,i.e., a diseased section of tissue.

Vector flush sizing catheter 10 is placed within aorta 602. Vector flushsizing catheter 10 is advanced into aorta 602, e.g., via the femoralartery via a femoral incision (not shown), in an unbent and straightstate similar to that illustrated in FIG. 1.

In accordance with this embodiment, once contrast flush holes 68 arelocated adjacent renal arteries 604, 606, distal bendable part 76 isbent, e.g., 180 degrees, as discussed above. Accordingly, opening 22 andcontrast flush holes 68 are located adjacent renal arteries 604, 606.

Once vector flush sizing catheter 10 is positioned where desired anddistal bendable part 76 is bent, contrast 60 is dispersed from vectorflush sizing catheter 10. As opening 22 is directly adjacent contrastflush holes 68, contrast 60 is dispersed with a high localconcentration.

Disbursement of contrast 60 allows visualization of renal arteries 604,606, aorta 602, aortic bifurcation 612 including common iliac arteries608, 610 using fluoroscopy. Further, radiopaque measuring markers 66 arealso visible using fluoroscopy. Radiopaque measuring markers 66 are usedas a scale to determine the length L of aorta 602 between renal arteries604, 606 and aortic bifurcation 612.

FIG. 7 is a partial cross-sectional view of vessel assembly 600including vector flush sizing catheter 10 of FIG. 6 after deployment ofan aortic bifurcated stent graft 702 in accordance with one embodiment.Aortic bifurcated stent graft 702 includes a main body 704, a short,e.g., first, leg 706, and a long, e.g., second, leg 708.

Main body 704 extends from a proximal end 710 of aortic bifurcated stentgraft 702 to legs 706, 708. Main body 704 defines a main lumen 712.Short leg 706 extends from main body 704 to a distal end 714 of shortleg 706. Long leg 708 extends from main body 704 to a distal end 716 oflong leg 708. Legs 706, 708 define branch lumens 718, 720, respectively.Main lumen 712 is bifurcated into branch lumens 718, 720. Aorticbifurcated stent graft 702 includes graft material 722 and one or morestent rings 724.

In one embodiment, a plurality of aortic bifurcated stent grafts ofdifferent lengths are available to the clinician. Based upon themeasurement of the length L of aorta 602 between renal arteries 604, 606and aortic bifurcation 612 as measured using vector flush sizingcatheter 10, a particular length aortic bifurcated stent graft 702 isselected.

Aortic bifurcated stent graft 702 is deployed adjacent and distal torenal arteries 604, 606 such that long leg 708 extends into common iliacartery 610. Aortic bifurcated stent graft 702 spans and thus excludesaneurysm 614. In one embodiment, vector flush sizing catheter 10 and/orcontrast 60 dispersed therefrom facilitate accurate placement of aorticbifurcated stent graft 702.

Aortic bifurcated stent graft 702 is deployed such that vector flushsizing catheter 10 is located between aortic bifurcated stent graft 702and the wall of aorta 602.

FIG. 8 is a partial cross-sectional view of vessel assembly 600including vector flush sizing catheter 10 of FIG. 7 during deployment ofa contralateral limb in accordance with one embodiment. Once aorticbifurcated stent graft 702 is deployed, distal bendable part 76 is againstraightened as illustrated in FIG. 8. Vector flush sizing catheter 10is withdrawn, sometimes called relocated, to be distal to distal end 714of short leg 706. Vector flush sizing catheter 10 is then bent,sometimes called steered, to aim into distal end 714 and branch lumen718 of short leg 706.

A guide wire 802 is advanced through vector flush sizing catheter 10,through short leg 706, and into/through main body 704. A delivery system804 including a contralateral limb is advanced through vector flushsizing catheter 10 and over guide wire 802 into short leg 706. Thecontralateral limb is then deployed from delivery system 804 and withinshort leg 706 and common iliac artery 608. Delivery system 804,guidewire 802, and vector flush sizing catheter 10 are then removed.

As set forth above, vector flush sizing catheter 10 is used initially todisperse contrast 66 and measure the length L of aorta 602 between renalarteries 604, 606 and aortic bifurcation 612. After deployment of aorticbifurcated stent graft 702, vector flush sizing catheter 10 is used toguide and introduce another endovascular device, e.g., guidewire 802and/or delivery system 804, into aorta 602. By using vector flush sizingcatheter 10 for both procedures, the exchange of catheters, thecomplexity of the procedure, and the associated risks are minimized.

Although guidewire 802 and delivery system 804 are set forth as examplesof endovascular devices, in other embodiments, vector flush sizingcatheter 10 is used to steer and guide other endovascular devices suchas endovascular anchors, branch stent graft, or other endovasculardevices.

Further, vector flush sizing catheter 10 can be used for allEndovascular Aneurysm Repair (EVAR) and Thoracic Endovascular Aorticrepair (TEVAR) procedures. Vector flush sizing catheter 10 is used by aphysician as one catheter for the entire EVAR/TEVAR case versus multipleexchanges. Vector flush sizing catheter 10 can be used with allstent-grafts in addition to other vascular/IR procedures. There ispotentially less blood loss, less catheter exchanges, and an easierprocedure for the doctor. Also, there is the potential for quicker casetimes.

In one embodiment, vector flush sizing catheter 10 is 5 French (F),although other sizes such as 6 F, 6.5 F are used in other embodiments.This maximizes the anatomical applications for vector flush sizingcatheter 10.

The length of vector flush sizing catheter 10 is 65 or 100 cm dependingupon the anatomical location of desired use in one embodiment.

It should be understood that various aspects disclosed herein may becombined in different combinations than the combinations specificallypresented in the description and accompanying drawings. It should alsobe understood that, depending on the example, certain acts or events ofany of the processes or methods described herein may be performed in adifferent sequence, may be added, merged, or left out altogether (e.g.,all described acts or events may not be necessary to carry out thetechniques). In addition, while certain aspects of this disclosure aredescribed as being performed by a single module or unit for purposes ofclarity, it should be understood that the techniques of this disclosuremay be performed by a combination of units or modules associated with,for example, a medical device.

What is claimed is:
 1. A catheter comprising: a handle; a guide tubecoupled to the handle; a guide passage extending through the handle andthrough the guide tube; a steering assembly configured to deflect adistal bendable part of the guide tube; and at least one contrast flushhole in a straight part of the guide tube.
 2. The catheter of claim 1wherein the at least one contrast flush hole extends from an innersurface to an outer surface of the guide tube.
 3. The catheter of claim1 wherein the at least one contrast flush hole extends from the guidepassage through the entirety of the guide tube in a radial direction. 4.The catheter of claim 1 wherein the at least one contrast flush holecomprises a plurality of contrast flush holes at a particular locationalong a longitudinal axis of the guide tube.
 5. The catheter of claim 4wherein the contrast flush holes are opposite one another.
 6. Thecatheter of claim 1 wherein the at least one contrast flush holecomprises a plurality of contrast flush holes at two or more locationsalong a longitudinal axis of the guide tube.
 7. The catheter of claim 1wherein the contrast flush holes comprise a first pair of contrast flushholes at a first location along a longitudinal axis of the guide tubeand a second pair of contrast flush holes at a second location along thelongitudinal axis.
 8. The catheter of claim 7 wherein the first pair ofcontrast flush holes is radially offset from the second pair of contrastflush holes.
 9. The catheter of claim 1 wherein when the distal bendablepart of the guide tube is bent, an opening at a distal end of the guidetube is directly adjacent the at least one contrast flush hole.
 10. Thecatheter of claim 1 further comprising a plurality of regularly spacedapart radiopaque measuring markers on the guide tube.
 11. A cathetercomprising: a handle; a guide tube coupled to the handle; a guidepassage extending through the handle and through the guide tube; asteering assembly configured to deflect a distal bendable part of theguide tube; and a plurality of regularly spaced apart radiopaquemeasuring markers on a straight part of the guide tube.
 12. The catheterof claim 11 wherein each of the radiopaque measuring markers comprises acomplete circle extending around the circumference of the guide tube ina plane perpendicular to a longitudinal axis of the guide tube.
 13. Thecatheter of claim 11 wherein a fixed distance between each of theradiopaque measuring markers exists.
 14. The catheter of claim 13wherein the fixed distance equals 1 cm and there are twenty of theradiopaque measuring markers.
 15. The catheter of claim 11 wherein theradiopaque measuring markers comprise a first radiopaque measuringmarker and an adjacent second radiopaque measuring marker, the catheterfurther comprising: at least one contrast flush hole between the firstradiopaque measuring marker and the second radiopaque measuring marker.16. A method comprising: bending a distal bendable part of a guide tubeof a catheter so that an opening at a distal end of the guide tube isdirectly adjacent at least one contrast flush hole in the guide tube;dispersing contrast through the opening and the at least one contrastflush hole; visualizing radiopaque measuring markers on the guide tube;and guiding an endovascular device through a guide passage of the guidetube.
 17. The method of claim 16 further comprising: advancing the guidetube in a straight state into a main vessel such that the at least onecontrast flush holes is adjacent a branch vessel.
 18. The method ofclaim 17 wherein the visualizing further comprises visualizing thebranch vessel, the main vessel, and a bifurcation of the main vessel.19. The method of claim 18 further comprising using the radiopaquemeasuring markers to determine a length of the main vessel between thebranch vessel and the bifurcation.
 20. The method of claim 16 furthercomprising, prior to the guiding: straightening the distal bendable partof the guide tube; relocating the catheter; and steering the guide tubewith the distal bendable part.